Yet another Calcium Reactor question

[fener103]

Running a GEO 612 reactor on my 120G setup, parameters as follows:
Alk 11.5 DKH (Salifert)
Ca 460 (Elos)
PH 7.8-8

Running around 50 BPM
Approximately 55ML on the effulent per minute
Reef Fanatic controller set at 6.8

My question is to me my alk and calcium are a little on the high side and my PH is a little on the low side. I have made numerous small adjustments over the last two weeks and everything is running fairly stable. I would like to make a small adjustment to bring the PH up and the ALK and CA down. What is the best way to bring everything into line?

 

[grouper therapy]

I think you are running too much effluent out and in turn are releasing a lot of co2 into your system.I would gradually slow the effluent down over the course of a week and at the same time slowly adjust the ph level to around 6.5. I think you will see a slight decrease in alk levels , calcium should stay close to the same and maybe an increase in ph .

 

[lilrobb]

grouper therapy;544636 wrote: I think you are running too much effluent out and in turn are releasing a lot of co2 into your system.I would gradually slow the effluent down over the course of a week and at the same time slowly adjust the ph level to around 6.5. I think you will see a slight decrease in alk levels , calcium should stay close to the same and maybe an increase in ph .

+0.5
the GEO 612 is a single stage - you could probably add a second stage and raise the pH more before the effluent hits the tank.

 

[jef4y]

A second media chamber will help a little, but not all that much. Personally, I run my reactor at 6.8-7.1 as measured in the main chamber. I do this off of 30BPM and 50ml/min drip. I forget the brand of media I use, but I use the stuff that's commercially available from BRS or wherever. A lot of people have said that media won't dissolve until low 6's pH, and personally I can dissolve it just fine at 6.8-7.1.

Having a low pH sometimes happens due to a calcium reactor. Right now my pH is on the low side, running 7.7-7.8. According to Randy Holmes-Farley (chemist guru) of Reefkeeping.com, he mentions several things, one of which being to add a bit of limewater/kalkwasser to the tank to raise the pH. This can be done without substantially affecting the calcium or alkalinity as the dose should be MUCH smaller than a maintenance dose without a calcium reactor. Basically the kalk is used to absorb excess C02 and raise pH.

The one thing that stands out in your setup is the BPM of 50. That seems quite high IMHO, but if that is what's needed to maintain the pH in your reactor, then that's what is needed...

If you want to dial back your KH & CA a bit, you may want to lower your effluent drip back to 40-50 ml/min, and drop your bubble count or raise your pH in the reactor itself just a bit.

Whatever you do, make *SMALL* changes wait ONE DAY, test, tweak again. Keep notes through all of it. What you can't do is make a couple of changes. A CA reactor takes a few days at bare minimum up to a couple of weeks to really dial in right. Being methodical and keeping notes as well as daily testing is really a requirement.

 

[grouper therapy]

I would add a kalkwasser reactor to the system and then adjust the calcium reactor to those levels . The two used together provides a nice balance. MRC makes a super nice Nielsen kalk reactor.

 

[grouper therapy]

I can tell you this, when I set up my reactor I viewed it as an alk reactor and then set the ph to adjust the calcium levels which did effect the alk some but not as much as the calcium levels. The only other thing to really take notice of is the calibration of the ph probe. I have seen people set the ph to advised levels and it not be as effective as it should be since very few probes are calibrated often enough.